BaCu2V2O8: Quasi-one-dimensional alternating chain compound with a large spin gap

The new quasi-one-dimensional spin gap compound ${\mathrm{BaCu}}_2{\mathrm{V}}_2{\mathrm{O}}_8$ was studied by means of magnetic susceptibility and heat capacity measurements on a powder sample. The magnetic susceptibility was well reproduced by alternating antiferromagnetic chain model with $J_1=260\mathrm{K}$ and $J_2=52\mathrm{K}$, which result in a large spin gap of about $230\mathrm{K}$. It is suggested that the $J_1$ and $J_2$ are ascribable to interactions along the $\mathrm{Cu}\text{−}\mathrm{O}\text{−}\mathrm{V}\text{−}\mathrm{O}\text{−}\mathrm{Cu}$ path and the $\mathrm{Cu}\text{−}\mathrm{O}\text{−}\mathrm{Cu}$ path, respectively.